From the Guidelines
Ciprofloxacin is an effective antibiotic for treating wound infections caused by gram-negative rods. The typical adult dosage is 500-750 mg orally twice daily or 400 mg intravenously every 12 hours for 7-14 days, depending on infection severity 1. For empiric coverage of wound infections, ciprofloxacin may be combined with an agent effective against gram-positive organisms, such as clindamycin. Ciprofloxacin works by inhibiting bacterial DNA gyrase and topoisomerase IV, preventing DNA replication and ultimately killing the bacteria. It has good tissue penetration and broad coverage against common gram-negative pathogens including Pseudomonas aeruginosa, E. coli, Klebsiella, and Enterobacter species.
Some key points to consider when treating wound infections with gram-negative rods include:
- The use of antibiotics such as ciprofloxacin, which has been shown to be effective against a range of gram-negative pathogens 1
- The importance of wound care, including debridement, cleaning, and appropriate dressing changes, alongside antibiotic therapy
- The need to obtain cultures before starting antibiotics whenever possible to guide targeted therapy
- The potential for combination therapy with agents effective against gram-positive organisms, such as clindamycin
Other effective options include:
- Third-generation cephalosporins (ceftazidime)
- Carbapenems (meropenem)
- Piperacillin-tazobactam, particularly for more severe infections
- Fluoroquinolones, such as levofloxacin or moxifloxacin, which may be used as alternatives to ciprofloxacin 1
It's worth noting that the most recent and highest quality study, published in 2024 1, provides recommendations on first- and second-choice antibiotics for empiric treatment of clinical infections, including skin and soft tissue infections. However, the study does not specifically address the treatment of wound infections caused by gram-negative rods. Therefore, the recommendation to use ciprofloxacin is based on the available evidence from previous studies 1.
From the FDA Drug Label
Piperacillin and tazobactam is an antibacterial drug [see Microbiology (12.4)]. The pharmacodynamic parameter for piperacillin and tazobactam that is most predictive of clinical and microbiological efficacy is time above MIC. Piperacillin and tazobactam are widely distributed into tissues and body fluids including intestinal mucosa, gallbladder, lung, female reproductive tissues (uterus, ovary, and fallopian tube), interstitial fluid, and bile.
Piperacillin-tazobactam is effective for treating wound infections caused by gram-negative rods, as it has been shown to have antibacterial activity against a wide range of gram-negative bacteria, including Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and others 2.
- Key points:
- Piperacillin-tazobactam has a broad spectrum of activity against gram-negative bacteria.
- It is effective against many strains of gram-negative rods, including Pseudomonas aeruginosa.
- The pharmacodynamic parameter that is most predictive of clinical and microbiological efficacy is time above MIC.
Alternatively, levofloxacin also has activity against gram-negative bacteria, including Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and others 3.
- Key points:
- Levofloxacin has a broad spectrum of activity against gram-negative bacteria.
- It is effective against many strains of gram-negative rods, including Pseudomonas aeruginosa.
- The mechanism of action of levofloxacin involves inhibition of bacterial topoisomerase IV and DNA gyrase.
From the Research
Effective Antibiotics for Wound Infections with Gram-Negative Rods
- Ceftazidime is effective in treating wound infections caused by gram-negative rods, including Pseudomonas aeruginosa, Proteus mirabilis, and Escherichia coli 4, 5, 6
- Ciprofloxacin is also effective against gram-negative rods and can be used as an alternative to ceftazidime 7
- Cefepime is another option for treating serious bacterial infections, including those caused by gram-negative rods, and has been shown to be effective in clinical trials 8
Key Findings
- Ceftazidime has been shown to be effective in treating skin and skin structure infections, including wound infections, with a clinical cure rate of 93% 5
- Ciprofloxacin has been shown to be as effective as ceftazidime in treating serious infections, including those caused by gram-negative rods 7
- Cefepime has been shown to be effective in treating serious bacterial infections, including those caused by gram-negative rods, with a clinical cure rate of 92% 8